Wire-drawing machine



A.A G. BLODGETT WIM-DRAWING MACHINE July 29, `1.941.

` Filed Dec. s', i959y Z af Patented July 29, 1941 WIRE-DRAWING MACHINEAlbert G. Blodgett, Worcester, Mass., assigner to Morgan ConstructionCompany, Mass., a corporation of Massachusetts Worcester,

Application December 8, 1939, Serial No. 308,223

3 claims.' (ci. 205-14) This invention relates to wire-drawing machines,and more particularly to machines of the type having a series of diesthrough which the wire is drawn by means of rotating drums or blocks toeifect successive reductions of the wire.

It has been recognized heretofore that certain advantages arise from themaintenance of an appreciable tension in the wire -between each drum andthe V.succeeding die. This so-called bac tension not only decreases thepower required to drive the machine, but it also prolongs the life ofthe dies by reducing the die friction and the resultant heat, and makesit pos-4 sible to draw wire at higher speeds. While atdrum I0 draws theWire through the rst die I4, the wire then passing through the die lI5to the drum II and thence through the die I6 to the drum I2, whichserves as a nishing drum. The drum Ii) is driven by a motor I 8 which isconnected to the drum by means of suitable gearing I9. Similarly, thedrumII is drivenby a motor through the medium of gearing 2|.

The nishing drum I2 is driven by a motor 23 which is connected to thedrum by means of gearing 24. The rate at which the wire passes throughthe machine is determined by the speed of the nishing drum I2, which inturn is detery mined-by the speed of the motor V23. This motempts havebeen made to constructmachines which would operate in this'manner, theprior machines have ingeneral been complicated, expensive, unreliable,and diiilcult to maintain in proper adjustment. l

It is accordingly one object of the invention to provide a simple,inexpensive and reliable wiredrawing machine of the type havingrotatable drums to draw wire through a series of dies sucp applying apredetermined and readily adjustable torque to each of the drums.

It is a further object of lthe invention to provide a novel constructionfor a multiple die wiredrawing machine which is so arranged that thewire will neither slip on the drums nor continuously accumulate thereonduring the operation of the machine.

With these` and other objects in view, as will be apparent to thoseskilled in the artfthe in'- vention resides in the combination of partsset forth in the specication and covered by the claims appended hereto.

Referring to the drawing illustrating one embodiment of the invention,and in which like reference numerals indicate like parts,

Fig. 1 is'a somewhat diagrammatic view of a i wire-drawing machine; and

- Fig. 2 is an enlarged section taken on the line' j 2-,2 of Fig. 1. i

ltank 34.

tor may be an electric motor, and l't is preferablyv of the adjustablespeed type so that the rate of wire drawing may be controlled.

The motors I8 and 20 are hydraulic motors of the constant displacementtype. One suitable and well-known construction therefor is shown in Fig.2 and comprises a pair of intermeshing gearsf26-26 which are forced torotate by the pressure of the hydraulic iluid passing through 4themotor. A suitable fluid, such as oil, is supplied for the operation ofthe motors I8 and 20 through pipes 21 and 28 respectively from apreure-producing source.. such as a lpump v3|) driven by an electricmotor 3i. This pump may be of any suitable and well-known construction,and it may be supplied with oil through an inlet pipe 32 whichcommunicates with a reservoir or Pipes 35 serve to return the exhaustfluid from the motors -to the reservoir. Means is preferably provided tocontrol the pressure of the oil delivered by the pump, and for thispure' pose a by-pass 31 and'relief valve 38 are provided between thepump outlet and the exhaust. One suitable construction for the reliefvalve 38 is disclosed in the patent to Terry, No. 1,863,035.

Means is provided'to regulate automatically the pressure of the oilsupplied'to the respective motors I8 and 20, thereby controlling thetorque which these motors will apply t0 the wire-drawing drums. For thispurpose a pressure reducing and regulating valve 40 is arranged tocontrol the ow through the pipe 21,v and a similar valve 4I is arrangedto control the flow through the pipe 28. Each of the valves 40 and 4I isprovided with a handwheel 42 for the purpose of adjust' ment. Thesevalves may be of any well-known type adapted to maintain asubstantiallyconstant predetermined delivery pressure, one suitableconstruction being disclosed in the patent to Temple. No. Re. 19,545.For convenience in adjustment,l pressure gauges 43 are connected to thepipes 21 and 28 to indicate the fluid pressure at the inlets of therespective hydraulic motors I8 and 20.

It will now be understood that with the apparatus as so far describedeach of the motors I8 and 20 will be supplied with operating fluid at asubstantially constant pressure, which may be predetermined by theadjustment of the handwheels 42. Consequently the torque applied to therespective drums IIJ and II will be predetermined and substantiallyconstant, since the motors are of the constant displacement type. Byproper selection of the applied torque it is possible to maintain apredetermined back tension in the wire immediately anterior to the diesI and I5. The speeds of the drums I0 and will be determined by the speedof the nishing drum y 30. Consequently the unloaded drum will opera-teat high speed, and the remaining hydraulically driven drum or drums willnot operate at all.

In order to overcome this difilculty Iprovide means whereby the flow ofpressure fluid through each hydraulic motor is prevented unless thecorresponding block is maintaining a tension in the wire anteriorthereto. For this purpose, as shown in Fig. 1, a valve is provided inthe pipe 21, this valve being operated by a solenoid 46, theconstruction being such that the valve will open when the solenoid is`energized andv A similar construction is provided in connection withthe second die I5 and the second block II, the pipe 28 having a valve 51therein which is 'operated by a solenoid 58 so arranged that the v'alvewill open when the solenoid is energized and close when the solenoid isde-energized. The solenoid 58 is connected to a source 59 of electricitythrough a switch 5| which is biased toward open position by a spring 52and shunted by a normally-open push button 53. The die I5 is slidable ona support 65 and connected to the switch 6| by means of a lever 66fulcrummed The operation of the invention will now be apparent from theabove disclosure. With the motor 3| running and no wire passing throughthe machine, the switches 49 and 5| will be held open by theirrespective springs 50 and 62, the solenoids 45 and 58 will bede-energized, and the valves 45 and 51 will be closed. Hence no fluidwill flow through the motors I8 and 29, and the blocks I0 and II will bestationary. To thread the machine, the operator will point the end ofthe wire, pass itthrough the rst die I4 and attach it by a suitableg'rip to the drum I0 in a well-known manner. He will then close the pushbutton 5|, which will energize the solenoid 46 and 'open the valve 45,admitting fluid to the motor I8. This will rotate the drinn I0, and drawthe wire through the die I4, which will slide'along its support 53 untilthe switch 49 is closed, so that the operator may release the pushbutton without de-energizing the solenoid. When a suiiicient number ofwraps of wire have been formed about the drum III, the operator willstop the machine yby stopping the electric motor 3|. H e will thenre-point the wire, pass it through the second die I5, and attach it by asuitable grip to the second drum II. Then by starting the motor 3| andclosing the push button 63 momentarily, he can draw the wire through thedie I5. In case the wire slackens suiiiciently to4 allow rearwardmovement of the rst die I4, it may be necessary to close the push button5I also. When the desired number of wraps have been formed about thedrum II, the motor 3| will be stopped, and the wire will be repointed,passed through the die I6, and attached by a grip to the finishing drumI2. By starting both the motors 3| and 23, and if necessary closing thepush button 63 momentarily, several turns of wire may be formed aboutthe drum I2. 'I'he machine will then be stopped and the grip removed.This completes the threading of the machine. The operator will nowdecrease the pressure at the delivery side of the automatic valves 40and 4I to predetermined values by turning their respective handwheels42, whereupon he will start the electric motors 3| and 23. The machinewill proceed to draw wire through the several dies, with a predeterminedback tension in the wire anterior to each of the dies I5 and I6, thespeed of the wire being controlled by the speed of the motor 23. Therewill be no accumulation of wire except on the finishing drum, and noslipping between the wire and the drums. The hydraulic motorsoperatewith predetermined luid pressures and a constant displacement,and hence will transmit predetermined torques to their respective drums.As the tail end of the wire passes through the flrst die I4, all loadwill be removed from the rst drum I0 and its driving motor I8. Thespring 50 will immediately open the switch 49, deenergizing the solenoid46 and closing the valve 45. This will prevent fluid from entering themotor I3, so that this motor will stop, instead of accelerating to ahigh speed (as would otherwise occur), and full Afluid pressure will bemaintained for operation of the motor 20.' The wire will loosen aboutthe drum I0 and will be with-` drawn therefrom by the continued rotationof the drum II. As the tail end of the wire passes the die |5, thespring 62 will open the switch 5I, de-energizing the solenoid 53 andclosing the valve 51. This will stop the drum II, and the wire will bewithdrawn therefrom by the continued rotation of the finishing drum I2.The

motor 23 will then be stopped, the finished wire will be removed fromthe drum I2l and the machine will be re-threaded as before.

at a predetermined pressure. It necessarily follows'that the backtension between the drum' I and the second die l5 will be predetermined,since it is equal to the diierence between the constant tension anteriorto the drum and the predetermined force applied to the wire bythe drum.Similarly, the tension between the die l and the drum Il will bepredetermined, since it is the sum of the predetermined back tensionanterior to the die I5 and the constant reactive force of the die.predetermined force to the wire, it necessarily follows that the backtension between this drum and the following diev I6 is predetermined,this back tension being equal to the difference between-twopredetermined forces. In this connection it will of course be recognizedthat under all normal conditions, with the drums neither accelerating ordecelerating, the tangential forces on the drums are in equilibrium.

It will now be apparent that the invention provides a dependablemultiple-die machine of Sincethe drum Il applies a.

a comparatively simple and inexpensive construction adapted-to draw wirewith a predetermined back tension andwithout slipping of the wire on thedrums. The pressure reducing and regulating valves 40 and 4| lare of astandard construction Which can be obtained commercially atcomparatively low cost. 'I'he hydraulic motors I8 and 20 are relativelyinexpensive, since they are of the constant displacement type whichrequires no complicated adjusting mechanism.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. A wire-drawingI machine comprising a plurality of dies, a pluralityof rotatable drums to -`draulic motors each of which is connected vtoanother of the drums to drive the same, and means to supply uid to eachof the motors at an independently adjustable predetermined pressure. v

2. A wire-drawing machine comprising a plurality of dies, a plurality ofrotatable drums to draw wire through the dies successively, means todrive one of the drums at a. predetermined speed, a plurality ofconstant displacement hydraulic motors each of which is connected toanother of the drums to drive the same, means to supply operating fluidto the motors, and a separate vpressure reducing and regulating valveassociated with each mfotor to controlthe pressure of the operatingfluid supplied thereto.

3. A wire-drawing machine comprising a plurality of dies, a plurality ofrotatable drums to draw ,wire through the dies successively, means todrive one of the drums -at a,predetermined speed, a plurality ofconstant displacement hydraulic motors each of which is connected toanother of the drums to drive the same, means providing a supply ofoperating uid, pipesconnecting the iiuid supplymeans with the respec-'tive hydraulic motors, and a separate pressure reducing and regulatingvalve in each pipe to control Vindependently the pressure of the uid

